feat: bump to v0.1.23 with security metrics and UI improvements

- Bump agent and server versions to 0.1.23
- Implement security metrics collection (bound agents, command processing, version compliance)
- Add dismiss button for timed out commands in agent status
- Add config sync endpoint for server->agent configuration updates
- Add ignored updates workflow in AgentUpdatesEnhanced (approve/reject workflow)
- Swap AgentScanners layout (subsystems top, security bottom)
- Replace placeholder security data with database metrics
- Add backpressure detection based on pending command ratios

aggregator-agent/cmd/agent/main.go

@@ -28,7 +28,7 @@ import (
 )
 
 const (
-	AgentVersion = "0.1.22" // v0.1.22: Machine binding and version enforcement security release
+	AgentVersion = "0.1.23" // v0.1.23: Real security metrics and config sync
 )
 
 var (